Bilateral knee periprosthetic infection with Mycobacterium fortuitum.

Periprosthetic infections after total joint arthroplasty are infrequent but potentially devastating complications. Gram-positive bacteria is the typical causative organism. However, uncommon sources such as Mycobacterium fortuitum have been documented in the literature. We report a case, the first to our knowledge, of bilateral infections involving this organism after total knee arthroplasty. M. fortuitum is notoriously resistant to many standard antibacterial medications, and a delay in initial diagnosis due to inadequate incubation time has been reported. In poor surgical candidates, long-term antibiotic suppression may be a viable alternative.